Trauma Practice Questions

Q: All of the following are true about dashboard injuries EXCEPT?

The point of impact is on the greater trochanter.. ### Explanation **1. Why Option D is the Correct Answer (The Exception)** In a **dashboard injury**, the point of impact is **not** the greater trochanter. Instead, the force is applied to the **proximal tibia (knee)** while the hip and knee are flexed (as seen in a seated passenger during a head-on collision). This longitudinal force is transmitted along the shaft of the femur toward the hip joint. Because the hip is flexed and adducted in this position, the femoral head is driven posteriorly, out of the acetabulum. Impact on the greater trochanter is typically associated with lateral compression injuries or femoral neck fractures, not classic dashboard dislocations. **2. Analysis of Other Options** * **Option A:** Dashboard injuries are the classic mechanism for **posterior dislocation of the hip** (the most common type of hip dislocation). * **Option B:** The **sciatic nerve** (specifically the peroneal division) lies immediately posterior to the acetabulum. During a posterior dislocation, the femoral head can compress or stretch the nerve, resulting in **foot drop**. * **Option C:** **Avascular Necrosis (AVN)** is a dreaded late complication. The blood supply to the femoral head (via the retinacular vessels) is disrupted during dislocation. The risk of AVN increases significantly if the dislocation is not reduced within 6 hours. **3. NEET-PG Clinical Pearls** * **Position of the Limb:** In posterior hip dislocation, the limb is typically **shortened, adducted, and internally rotated**. (Contrast this with anterior dislocation: abducted and externally rotated). * **Associated Fracture:** Often associated with a fracture of the **posterior lip of the acetabulum**. * **Management:** It is an **orthopaedic emergency**. The first-line treatment is closed reduction (e.g., Allis maneuver or Bigelow's maneuver) under sedation. * **Most Common Nerve Injured:** Sciatic nerve (10-20% of cases).

Q: Which test is used for posterior dislocation of the glenohumeral joint?

Jerk test. The **Jerk test** is the specific clinical maneuver used to assess **posterior instability** and posterior labral tears of the glenohumeral joint. ### **Explanation of Options** * **A. Jerk Test (Correct):** To perform this, the patient’s arm is placed in 90° of abduction and internal rotation. The examiner applies an axial load to the humerus while moving the arm into horizontal adduction. A positive result is a sudden "jerk" or "clunk" as the humeral head subluxates posteriorly over the glenoid rim. * **B. Fulcrum Test:** This is used to diagnose **stress fractures of the femoral shaft**. The examiner’s arm acts as a fulcrum under the patient's thigh while downward pressure is applied to the knee. * **C. Crank Test:** This is used to identify **SLAP (Superior Labrum Anterior to Posterior) lesions**. It involves axial loading and rotation of the humerus in an elevated position. * **D. McMurray’s Test:** A classic physical exam maneuver used to diagnose **meniscal tears** in the knee joint, not the shoulder. ### **High-Yield Clinical Pearls for NEET-PG** * **Posterior Dislocation:** Often associated with **seizures** or **electric shocks**. On X-ray, look for the **"Light bulb sign"** (due to internal rotation) and the **"Rim sign"**. * **Kim Test:** Another specific test for posteroinferior labral tears, often performed in conjunction with the Jerk test. * **Anterior Instability:** The most common type of shoulder dislocation. Key tests include the **Apprehension test**, **Relocation test**, and **Surprise test**. * **Bankart Lesion:** Avulsion of the anteroinferior labrum; **Hill-Sachs Lesion:** Compression fracture of the posterolateral humeral head (both seen in anterior dislocations).

Q: What is defined as a compound fracture?

Fracture with skin involvement. **Explanation:** A **compound fracture**, also known as an **open fracture**, is defined by a break in the skin and underlying soft tissues that leads directly to the fracture site or its hematoma. The hallmark of this condition is the communication between the bone and the external environment, which significantly increases the risk of bacterial contamination and osteomyelitis. **Analysis of Options:** * **Option D (Correct):** Skin involvement is the defining feature. If the skin is breached, the fracture is "open" or "compound." This requires urgent surgical debridement and antibiotic prophylaxis. * **Option A:** All fractures, by definition, involve bone. This is a redundant description of a simple fracture. * **Option B:** Nerve involvement characterizes a "fracture with neurological deficit" (e.g., Holstein-Lewis fracture involving the radial nerve). While serious, it does not make a fracture "compound." * **Option C:** Most fractures involve some degree of muscle contusion or strain, but this is classified under soft tissue injury, not as a compound fracture. **NEET-PG High-Yield Pearls:** 1. **Gustilo-Anderson Classification:** This is the gold standard for grading open fractures (Type I to IIIC) based on wound size, soft tissue damage, and vascular injury. 2. **Golden Period:** The first **6 to 8 hours** post-injury is the critical window for debridement to prevent established infection. 3. **Management Priority:** "Life before limb." Follow ATLS protocols, then prioritize wound irrigation, splinting, and IV antibiotics (usually cephalosporins). 4. **Tetanus Prophylaxis:** Always mandatory in the management of any compound fracture.

Q: A young college student injures his left knee while playing football and is unable to bear weight. The provisional X-ray report indicates that there are no fractures seen. He presents the next morning to the emergency department with a severely swollen, painful left knee and severe pain in the foot. On examination, the foot is pale, cold, and pulseless. What is the most likely diagnosis?

Posterior knee dislocation with thrombosed popliteal artery. ### Explanation **1. Why Option D is Correct:** The clinical presentation of a high-energy knee injury followed by a **"pale, cold, and pulseless"** foot is a classic triad indicating **acute limb ischemia**. In the context of a knee injury without a fracture, the most critical diagnosis to rule out is a **knee dislocation**. Even if the knee has spontaneously reduced (explaining why X-rays might appear normal), the popliteal artery is tethered at the adductor hiatus and the soleal arch, making it highly susceptible to intimal tears or thrombosis during the displacement. The severe swelling and inability to bear weight further support a major ligamentous disruption (dislocation). **2. Why Other Options are Incorrect:** * **A. Traumatic DVT:** DVT typically presents with a warm, swollen, and cyanotic limb (phlegmasia), not a cold, pale, and pulseless one. It does not cause an acute loss of arterial pulses. * **B. Gastrocnemius muscle tear:** While common in sports, this causes localized calf pain and swelling. It would not result in global foot ischemia or loss of distal pulses. * **C. Traumatic AV Fistula:** This usually presents chronically with a thrill, bruit, or venous insufficiency. It does not cause acute, limb-threatening ischemia immediately following trauma. **3. Clinical Pearls for NEET-PG:** * **"The Knee that Reduced":** Always suspect a knee dislocation in high-energy trauma even if X-rays are normal; 50% reduce spontaneously before reaching the ER. * **Popliteal Artery:** It is the most commonly injured artery in knee dislocations (up to 40% of cases). * **Management Priority:** If pulses are absent, the next step is urgent surgical exploration or CT Angiography. The "Golden Period" for revascularization is **6 hours** to prevent amputation. * **Peroneal Nerve:** The most common nerve injured in knee dislocations (leads to foot drop).

Q: Which of the following is NOT an intra-articular fracture?

March fracture. **Explanation:** The core concept tested here is the anatomical location of specific fractures relative to the joint capsule. An **intra-articular fracture** is one where the fracture line extends into the joint surface, often leading to long-term complications like post-traumatic osteoarthritis if not perfectly reduced. **Why March Fracture is the correct answer:** A **March fracture** is a stress fracture of the metatarsal shaft (most commonly the 2nd or 3rd metatarsal). It occurs due to repetitive microtrauma, typically in military recruits or long-distance hikers. Because it involves the **diaphysis (shaft)** of the bone and does not involve the joint surface, it is an extra-articular fracture. **Analysis of incorrect options:** * **Bennett’s Fracture:** This is an oblique, **intra-articular** fracture at the base of the 1st metacarpal. It involves a single volar lip fragment that remains attached to the anterior oblique ligament. * **Rolando Fracture:** This is a comminuted (T or Y-shaped), **intra-articular** fracture at the base of the 1st metacarpal. It is essentially a more complex version of Bennett's fracture and carries a worse prognosis. * **Barton’s Fracture:** This is an **intra-articular** fracture-dislocation of the distal radius involving the dorsal or volar rim. It must be distinguished from Colles' or Smith's fractures, which are extra-articular. **Clinical Pearls for NEET-PG:** * **Bennett vs. Rolando:** Both occur at the base of the thumb; Bennett is 2-part (simple), Rolando is 3-part or more (comminuted). * **March Fracture Diagnosis:** Initial X-rays are often negative; a bone scan or MRI is more sensitive in early stages. Callus formation on X-ray after 2–3 weeks is a classic finding. * **Management:** Intra-articular fractures (Bennett, Rolando, Barton) usually require **ORIF** (Open Reduction Internal Fixation) to restore joint congruicity, whereas March fractures are managed conservatively with rest.

Q: What is the most common complication of a Colles fracture?

Stiffness of fingers. **Explanation:** **Colles fracture** is a distal radius fracture occurring within 2.5 cm of the wrist joint, characterized by dorsal displacement and angulation (dinner fork deformity). **1. Why Stiffness of Fingers is the Correct Answer:** Stiffness of the fingers and shoulder is the **most common complication** of a Colles fracture. This occurs primarily due to prolonged immobilization in a plaster cast and the patient’s reluctance to move the fingers during the healing phase. Edema and lack of muscle pump action lead to adhesions around the small joints of the hand. Early mobilization of the fingers is the most critical step in preventing this complication. **2. Analysis of Incorrect Options:** * **B. Malunion:** This is the **most common late complication** of Colles fracture, often resulting in a "dinner fork deformity." While frequent, finger stiffness remains the most prevalent clinical issue affecting functional outcomes. * **C. Sudeck’s Osteodystrophy (CRPS Type 1):** This is a serious complication characterized by pain, swelling, and vasomotor instability. While it is a classic association with Colles fracture, it is not as common as simple joint stiffness. * **D. Rupture of EPL Tendon:** This is a **delayed complication** (usually occurring 4–8 weeks post-injury) caused by ischemia or attrition of the Extensor Pollicis Longus tendon at Lister’s tubercle. It is relatively rare. **Clinical Pearls for NEET-PG:** * **Most common complication:** Stiffness of fingers/shoulder. * **Most common late complication:** Malunion. * **Most common nerve involved:** Median nerve (Carpal Tunnel Syndrome). * **Treatment of choice:** Closed reduction and below-elbow cast (Colles cast). * **Deformities in Colles:** Dorsal tilt, Lateral tilt, Supination, Impaction, and Radial deviation.

Q: Which of the following is true about fat embolism?

Usually ensues after fracture of the lower limb. **Explanation:** **Fat Embolism Syndrome (FES)** is a clinical diagnosis characterized by the systemic release of fat globules into the circulation. 1. **Why Option A is Correct:** Fat embolism most commonly follows fractures of **long bones**, particularly the **femur and tibia** (lower limbs), and the pelvis. These bones contain large amounts of fatty yellow marrow. Trauma disrupts the intramedullary pressure, forcing fat droplets into the venous sinusoids. 2. **Why Option B is Incorrect:** While subclinical fat embolism occurs in nearly 90% of all major fractures, the clinical *syndrome* (FES) is a **common and serious complication** rather than an "uncommon" one in the context of high-energy trauma. It is a leading cause of morbidity in orthopedic patients. 3. **Why Option C is Incorrect:** FES is **not** a spontaneously reversible process in the sense of being benign. It is a potentially fatal condition (mortality rate 5-15%) that requires aggressive supportive care, including oxygenation and often mechanical ventilation. It does not simply "resolve" without clinical monitoring. **High-Yield Clinical Pearls for NEET-PG:** * **Gurd’s Criteria:** Used for diagnosis. Major criteria include **Respiratory insufficiency** (hypoxemia), **Cerebral involvement** (confusion/coma), and **Petechial rash** (typically over the chest, axilla, and conjunctiva). * **Latent Period:** Symptoms typically appear **24–72 hours** after the injury. * **Snowstorm Appearance:** Classic finding on Chest X-ray (diffuse bilateral pulmonary infiltrates). * **Treatment:** Primarily **supportive** (Maintenance of PaO2). Early stabilization/fixation of the fracture is the best preventive measure.

Question 1

All of the following are true about dashboard injuries EXCEPT?

Accepted Answer

The point of impact is on the greater trochanter.

Answer

It is associated with posterior dislocation of the hip.

Answer

Sciatic nerve may be involved, leading to foot drop.

Answer

Avascular necrosis of the hip could be a late complication.

Question 2

A 55-year-old woman presents with severe pain in the flexor muscles of the forearm, fixed flexion of the fingers, and swelling, cyanosis, and anesthesia of the fingers following a car crash. Which of the following is the most likely diagnosis?

Accepted Answer

Volkmann's ischemic contracture

Answer

Colles' fracture

Answer

Scaphoid fracture

Answer

Bennett's fracture

Question 3

Which test is used for posterior dislocation of the glenohumeral joint?

Accepted Answer

Jerk test

Answer

Fulcrum test

Answer

Crank test

Answer

McMurray's test

Question 4

What is defined as a compound fracture?

Accepted Answer

Fracture with skin involvement

Answer

Fracture with bone involvement

Answer

Fracture with nerve involvement

Answer

Fracture with muscle involvement

Question 5

In an undisplaced fracture of the neck of the femur, what is the ideal treatment?

Accepted Answer

Internal fixation

Answer

Skeletal traction

Answer

Femoral head prosthesis

Answer

Each of the above as similar prospects and results

Question 6

A young college student injures his left knee while playing football and is unable to bear weight. The provisional X-ray report indicates that there are no fractures seen. He presents the next morning to the emergency department with a severely swollen, painful left knee and severe pain in the foot. On examination, the foot is pale, cold, and pulseless. What is the most likely diagnosis?

Accepted Answer

Posterior knee dislocation with thrombosed popliteal artery

Answer

Traumatic deep vein thrombosis

Answer

Gastrocnemius muscle tear

Answer

Traumatic arteriovenous fistula

Question 7

Which of the following is NOT an intra-articular fracture?

Accepted Answer

March fracture

Answer

Rolando fracture

Answer

Bennett's fracture

Answer

Baon's fracture

Question 8

What is the most common complication of a Colles fracture?

Accepted Answer

Stiffness of fingers

Answer

Malunion

Answer

Sudeck's osteodystrophy

Answer

Rupture of EPL tendon

Question 9

Which of the following is true about fat embolism?

Accepted Answer

Usually ensues after fracture of the lower limb

Answer

An uncommon complication of fracture

Answer

A spontaneously reversible process

Answer

All of the above

Question 10

A patient presents with a tibia fracture and swelling of the lower leg. The pulse is feeble but palpable, and intracompartmental pressure is elevated. What is the next step in management?

Accepted Answer

Fasciotomy

Answer

External fixation

Answer

Lower limb venography

Answer

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Trauma — MCQs

Trauma — MCQs

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